With the advent of very large tractors with a high horsepower range, it has become common to use very long tool bars having earth working tools attached thereto at spaced intervals along such tool bar. Likewise, other crop treating devices, such as sprayers are attached to such long tool bars.
Because such tool bars are so long, it becomes necessary to fold such tool bars when it is desired to transport the device between the field in which it is being used and the place where it is to be stored, which necessitates movement through narrow gates and along public roads. For this reason, there have been numerous inventions relating to structures for folding such long tool bars in one way or another.
These very long tool bars which fold work just fine on level ground, but do not work satisfactorily on uneven ground because they tend to be designed to be rigid and straight when folded into a position for use in the field. That is to say, if the ground is uneven, then one part of the tool bar will be closer to the ground than another, thereby causing uneven working of the ground or, in the case of spraying equipment, causing the spraying operation to be uneven and therefore unsatisfactory.
There have been certain attempts to permit some flexing or variation of the wing sections of a folding tool bar with respect to the ground. The problem is that previous attempts to permit the wing sections of the tool bar to pivot up and down to conform to the variations in the level of the ground have been too complex and consequently expensive to produce and somewhat unreliable because of having too many moving parts. PG,4
Consequently, there is a need for an uncomplicated, reliable solution to the aforementioned problem.